IGCSE Sciences - Co-Ordinated (0973) — May–June 2024, Paper 21
40 questions · every question answerable online with instant point-by-point AI marking against the official mark scheme.
Start with Question 1 →Which processes are done by green plants? 1 detect stimuli and make appropriate responses 2 break down nutrient molecules to release energy for metabolism 3 take in carbon…
Answer this question and get it marked →Which conditions will result in the fastest rate of diffusion? A temperature high, concentration gradient large, diffusion distance short B high, small, long C low, small, short D…
Answer this question and get it marked →A sample of food is tested for reducing sugars by adding Benedict's solution and heating. What indicates that reducing sugars are present? A a blue-black colour B a brick-red…
Answer this question and get it marked →Which statement about denaturation is correct? A Denaturation is the change in shape of the active site of the enzyme at a pH above the optimum pH. B Denaturation is the change in…
Answer this question and get it marked →The diagram shows a cross-section of a leaf of a plant. The leaf is adapted to float on water with the upper epidermis exposed to the air. [Diagram: floating leaf; stomata are in…
Answer this question and get it marked →Humans have different types of teeth. Which type of tooth is used for biting off food? A canines B incisors C premolars D molars
Answer this question and get it marked →A student investigates the effect of humidity on transpiration rate. A plant is placed on a balance for one hour (with the pot sealed in a polythene bag). The mass of the plant…
Answer this question and get it marked →A pupil runs to school. What happens to the rate and depth of their breathing as they run? A rate decreases, depth decreases B rate decreases, depth increases C rate increases,…
Answer this question and get it marked →A person looks at a tree in the distance and then starts to read a book. Which changes occur in the eye to enable the person to read their book? A ciliary muscles contract,…
Answer this question and get it marked →Which row describes asexual reproduction? [Table: rows A-D marked yes/no against 'only one parent', 'fusion of nuclei', 'genetically identical offspring'. Asexual reproduction =…
Answer this question and get it marked →The diagram shows the inheritance of a disease (key: unaffected/affected males and females). Two unaffected parents have an affected child. [Pedigree diagram: unaffected parents…
Answer this question and get it marked →How does an organism in the first trophic level gain energy? A by absorbing energy from sunlight B by breaking down dead or waste organic matter C by eating organisms in the…
Answer this question and get it marked →The list shows changes that occur in a lake which is polluted by fertiliser. 1 Decomposers feed on aquatic plants. 2 Growth of algae increases. 3 Oxygen levels decrease in the…
Answer this question and get it marked →The initial and final readings on a sensitive thermometer used in an experiment are shown (initial about 21.7 C, final about 29.3 C). [Diagram: two thermometer readings, initial…
Answer this question and get it marked →The boiling point of ammonia is -33 C. The temperature of a sealed flask containing ammonia is changed from -35 C to -30 C. Which row describes and explains the type of change…
Answer this question and get it marked →Which dot-and-cross diagram represents the outer-shell electrons in a molecule of methanol? [Diagrams A-D: methanol CH3OH dot-and-cross; A shows correct shared pairs for C-H, C-O…
Answer this question and get it marked →Which statements describe the structure of silicon(IV) oxide? 1 Each oxygen atom is attached to two silicon atoms. 2 Each oxygen atom is attached to four silicon atoms. 3 Each…
Answer this question and get it marked →The equation for the combustion of magnesium is 2Mg + O2 - 2MgO. What is the mass of magnesium oxide formed from 12 g of magnesium? (Ar: Mg 24, O 16) A 20 g B 24 g C 40 g D 80 g
Answer this question and get it marked →Two electrolysis experiments are done using inert electrodes. Experiment 1 is the electrolysis of aqueous copper(II) sulfate. Experiment 2 is the electrolysis of molten lithium…
Answer this question and get it marked →A piece of sodium is added to water (2Na + 2H2O - 2NaOH + H2). Which row shows the type of reaction and the energy level diagram for the reaction? [Options A-D: type of reaction…
Answer this question and get it marked →Magnesium ribbon is reacted with 50 cm3 of dilute hydrochloric acid. Which change does not increase the rate of the reaction? A Increase the concentration of the hydrochloric…
Answer this question and get it marked →Which metal is used in the test for nitrate ions? A aluminium B copper C magnesium D tin
Answer this question and get it marked →Element X is a dense solid with a high melting point. Which letter shows the position of X in the Periodic Table? [Diagram: Periodic Table outline; A and B on the left/centre, C…
Answer this question and get it marked →Which statement about noble gases is correct? A All of the noble gas atoms have eight electrons in their outer shell. B They all form diatomic molecules. C Argon is used to fill…
Answer this question and get it marked →Which statements about the Haber process are correct? 1 The hydrogen used is obtained from the air. 2 The pressure used is about twice atmospheric pressure. 3 The catalyst used is…
Answer this question and get it marked →The structure of a molecule of compound X is shown (ethene, C2H4, with a C=C double bond). [Structure: ethene C2H4.] Which two formulas represent compounds that are in the same…
Answer this question and get it marked →Which molecules can be used as monomers in polymerisation processes? [Structures: 1 = chloroethene (an alkene, addition monomer), 2 = an alcohol, 3 = an amino acid (condensation…
Answer this question and get it marked →Which statement describes a system that is in equilibrium? A There is a resultant force and there is a resultant turning effect on the system. B There is a resultant force but…
Answer this question and get it marked →An irregularly shaped piece of aluminium is lowered into a measuring cylinder that contains 43 cm3 of water. The aluminium is totally immersed and the water level rises to 51 cm3.…
Answer this question and get it marked →An object of mass 5.0 kg falls vertically from rest through a height of 13 m in a vacuum. The gravitational field strength g is 10 N/kg. What is the final speed of the object? A…
Answer this question and get it marked →For which energy resource is the Sun not the source of the energy? A geothermal B natural gas C water behind a hydroelectric dam D wind
Answer this question and get it marked →In a room, hot air above a heater rises and is replaced by cool air that falls. What is the name of this process, and how does the density of the hot air compare with the density…
Answer this question and get it marked →A wave has an amplitude, a frequency and a wavelength. Three definitions are given. 1 the maximum displacement from the rest position 2 the number of wavefronts passing a point in…
Answer this question and get it marked →A thin converging lens produces a real image of an object. What happens to the image as the object is moved away from the lens? A It becomes larger and stays inverted. B It…
Answer this question and get it marked →A bar of soft iron and a bar of steel are held in contact with a strong magnet. Both bars become magnetised. The two bars are now moved away from the magnet. Which statement about…
Answer this question and get it marked →The current in an ammeter is 1.5 A. How much charge passes through the ammeter in one minute? A 0.025 C B 1.5 C C 40 C D 90 C
Answer this question and get it marked →Two resistors with different resistances are connected to a power supply. The resistors can be connected either in parallel or in series. Which statement is correct? A For…
Answer this question and get it marked →There is an alternating current (a.c.) in a metal wire. Which statement about the current is correct? A It is a flow of both positively and negatively charged particles. B It is a…
Answer this question and get it marked →A 100% efficient step-down transformer has 120 turns on its primary coil and 10 turns on its secondary coil. A 240 V supply provides 48 W of power to the primary coil. What is the…
Answer this question and get it marked →A proton has charge q and mass m. A neutron has no charge and mass m. Which row shows the charge and mass of an alpha-particle (2 protons and 2 neutrons)? A charge 2q, mass 2m B…
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